Perioperative implications of patients with alpha gal allergies

Abstract

Alpha Gal Syndrome (AGS) is an emerging immune response to mammalian products (MP) containing the oligosaccharide galactose-α-1,3 galactose (α-Gal) which includes meats and inactive ingredients in certain medications. This becomes clinically important in the perioperative realm as MPs are commonly found in the operating room, and pre- and post-operative settings, and can trigger responses as severe as anaphylaxis. In this review, authors discuss the epidemiology, diagnosis and treatment of AGS reactions. Additionally, strategies are explored in order to screen and prevent exposure to MP with a multidisciplinary approach. While this emerging allergy is still not fully understood, it is of paramount importance that all anesthesia providers recognize the implications of MP exposure in AGS patients and ultimately prevent harm in this highly vulnerable population.

Keywords: Alpha gal syndrome; Anesthesia; Heparin; Mammalian products; Red meat allergy; Surgery.

Figure 1:

Risk stratification algorithm for AGS patients requiring perioperative parenteral anticoagulation *Premedication regimen:

1. Prednisone 0.7mg/kg PO (max 50mg) at 13, 7, 1 hour preop if time allows. Omit if emergent case.

   1. Substitute with Hydrocortisone 1.5mg/kg IV (max 100mg) given as soon as possible preop if urgent/emergent case

2. Diphenhydramine 0.7mg/kgPO/IV (max 50mg) 1 hour preop or as soon as possible if urgent/emergent case

3. Cetirizine 0.25mg/kg (max 20mg) PO 13 hours preop. Omit if emergent case.

**Loading dose challenge defined as 10u/kg heparin IV and observing for 15 minutes. If no reaction, proceed with full loading dose. If positive reaction, switch to alternative anticoagulation strategy.